Some conventional data storage systems routinely buffer data in write caches before flushing the data out as stripes to data storage arrays. That is, when such a data storage system has enough data segments in its write cache to perform a full stripe write operation (e.g., four 64 KB data segments for 256 KB of total data), the data storage system computes a parity segment and then writes the data segments and the parity segment as a full stripe to the storage devices of the array (e.g., RAID Level 5 (4+1)).
It should be understood that some of the data that is written by a full stripe write operation may be an update of existing data. In such a situation, the data storage system updates metadata for the data so that the metadata now indicates that the data is located in the newly written stripe.